The present invention relates to the monitoring of computer systems, and more particularly to the monitoring of rack mounted computer systems.
FIG. 1 illustrates a conventional rack mounted computer system. The system comprises a container or rack 102 within which are mounted a plurality of computers 104.1-104.n. The video outputs of each of the computers 104.1-104.n are connected to an analog video multiplexer (MUX) 106 through cables 108.1-108.n. Thus, the conventional rack mounted computer system uses a parallel cabling scheme. The analog video MUX 106 is capable of receiving an analog video signal from one of the computers 104.1-104.n and displaying it onto a console 110 with a display device. Each computer 104.1-104.n must also have cables (not shown) running from outputs to a break-out box (not shown), the break-out box then connected to a keyboard and a mouse.
However, the analog video signals experience signal degradation as they are transmitted to the MUX 106, compromising the video quality at the console 110. Also, due to the analog nature of the video monitoring system, only a limited number of computers may be connected to a MUX. Thus, for large computer systems, such as those comprising thirty or forty computers, multiple MUX""s in multiple layers are required. This results in even greater signal degradation. With the parallel cabling scheme, these large computer systems are burdened with a heavy wiring mass.
Accordingly, there exists a need for improved video for a rack mounted computer system. This system should minimize signal degradation, decrease the amount of cables required, and reduce the total cost of the system. The present invention addresses such a need.
A method and system for providing a rack mounted computer system which transmits a digital video signal through multiple computers includes a plurality of computers and a plurality of cables connecting the plurality of computers in a serial manner, where the plurality of cables transmits a digital video signal from one of the plurality of computers. Each computer includes a planar video controller and a receiver. The computer selected for display at the console provides parallel data streams with it planar video controller. The computers not selected for display at the console receive the serial data stream from an upstream computer and converts it into the parallel data streams. The parallel data streams are multiplexed and converted in a serial data stream and transmitted to downstream computers. Eventually, the data stream from the selected computer is displayed at the console. By transmitting the video signals in a digital format, signal degradation is decreased, providing a clearer video signal at the display. By connecting the computers serially, short cable hops between the computers may be used, decreasing the cost in cable length. Such short cable hops are also physically easier to wire. Thus, the total cost of the system decreases.